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Trailing-Edge - PDP-10 Archives - SRI_NIC_PERM_SRC_3_19910112 - monitor/errmes.hlp
There is 1 other file named errmes.hlp in the archive. Click here to see a list.
to build a new errmes.bin file, 
load erbld+site+monsym/comp
save
delete the monsym.rel and monsym.unv files it made
get monsym.exe
start .ergo